This is a special report from ABC news. Hello I'm tired Hernandez in new York and this is an ABC news digital special report. A military jury convicted an army major a murder for the deaths of thirteen people. During -- killing Rampage of Fort Hood Texas back in 2009. The vicious shooting spree also left more than thirty others wounded ABC's Louis Martinez joins us now from the Pentagon -- What does this verdict -- for major Nadal Hassan. Well -- -- in major Hasan what it means is a potentially could face the death penalty which is. His stated goal to start this trial he always acknowledge that he was -- shooter that was actually never in doubt as. As -- has played out. He served as his own defense attorney. But really didn't participate in the case at all prosecution presenting more than ninety witnesses including witnesses. Experts and all he really it was question about three of them in just -- nick a couple of -- sentences to them. -- so he isn't likely wanting -- -- he wants the death penalty. He says he wants to be a martyr because -- thought that in carrying out the attacks back in November 2009 at Fort Hood. But he was carrying out some kind of Jihad against American troops are headed -- Iraq and Afghanistan. So now we move into the sentencing phase where prosecutors are going to try to prove. That he deserves the death penalty they want him to get the death penalty it -- -- on wants that'll see we'll see how this plays out. You know we acted as his own attorney during the trial something that is -- usual. And as you mentioned he didn't put up much of the dissents. What was the reasoning behind that really why did the judge allow it. It's interesting -- the judge they allowed he's had a defense team has been working by his side but just at the very end of the pretrial motions hearings. All the -- he said I want to serve my attorney she deliberated and said that he he was in good standing to carry out and service is to own defense attorney. I as the case played out you know what happens is when that happens is the defense counsel in this this -- and that kind of like stand by legal counsel. Well as the case went progressed over the last two weeks -- court martial. They kind of grew annoyed and said that in pretty good standing could not serve as his stand by counsel. Because they felt that -- the sun is just going through the motions here. -- trying to get the death penalty and using court martial as a means of getting that death penalty. The martyrdom that he seeking. So he says he wants the death penalty but is there any potential irony that his. Doing such a poor job intentionally on his own defense could undermine. That sentence. There is that potential. Partly because if he does get the death penalty -- one thing we have to -- -- There's going to be -- basically a mini trial goes on from now on. This is -- -- sentencing phase we just wrapped up the Bradley Manning case in that was the sentencing phase and ended up -- -- getting 35 years in military prison. What's gonna happen with -- -- here. Is that again the prosecution you can for spring in a more witnesses including shooting shooting victims some of whom we heard during the court -- -- just wrapped up. But. -- it goes to the -- this time because Manning chose. Trial by a judge he this time it's a trial by jury for his -- because that's what he wanted that has to be unanimous verdict. By the members of the jury. That he deserves the death penalty if he gets -- that penalty that triggers an automatic appeals process. And that could take a very long time you know the military hasn't executed anyone since 1961. Last you know he he did present -- -- defense. But he apparently wanted to do it in a different way the judge didn't allow that can you tell us what that was. Well that judge. Has been -- -- is a -- Osborne about it turning she has been very. Deliberate in. Her decision making in this case has been very complicated there's been arguments about whether he should have had a beard and in. It's about serving in uniform because he's still an army officer. Other questions about how much participation he had heard it to be his own defense counsel but ultimately when it came up at the very end she said that. He she Secret Service is defense counsel the based on the understanding of a lot but he cat which I think -- kind of basic. Not Nazis sophisticated. What what was his explanation for killing thirteen of his fellow soldiers obviously he talked about Jihad but what do we know about. The buildup to that moment and why he was in. Detected sooner. Well the prosecutor you know in the bill that this case -- -- talk that. The warning signs were there that his side they side army psychiatrist. I had presented -- points -- fellow classmates. That's just didn't make any sense kind of rambled on about an Islamic Jihad. It's kind of a slow boil. Is what is the common perception has -- what's interesting is that the judge in this case -- Osborne. Has kind of indicated could potentially. This wasn't really a long term pattern of his that it may have been a spike of anger that resulted in the shootings. And let's remember this it was just thirteen -- but also 32 others soldiers -- -- Wounded in the attack so he's been convicted today of thirteen counts of premeditated murder and 32 counts. Premeditated attempted murder which makes -- pretty serious case obviously. But I mean it's. It's going to be interesting weather. That it's a slight variation but the judge impacts. Her instructions to the jury. Wind made the sentencing phase wraps up -- -- couple weeks you know he himself used the word Jihad. And yet the prosecution decided not. To go for any kind of conviction under terrorism law why did they choose not to do that. Well that's been you know the terrorism aspect has been very. Difficult here you have some. In the military arguing why are the victims -- the victims -- not receiving. The the purple heart of the purple heart is what every. Military service member receives -- injured in combat -- in -- terrorist situation. In this case they have not received that. Award. -- been a matter of controversy she's reported on it with some of the victims. Who are upset by that on the sun and sitting here depending -- -- -- -- out there why prosecutors didn't pursue that. But it seems that they felt more comfortable and getting the murder charges that improving. The the terrorism. But you know we reported that Hasan had contacts with are all lucky. Who was the head. Of the Qaeda and -- -- peninsula backing in Yemen at the time that they had contacts and that Hasan was seeking counsel but how to do things. I I I would argue that if this this case had gone let's say -- amount it would have been a terrorism. Case made there but this year obviously day it went with the yet premeditated murder charges -- -- point. It out that the last time the military executed anyone was back in 1961. What are the odds now that. Hasan will be executed how long is the sentencing phase going to take and when do we expect a decision from that jury. -- at sentencing phase probably take a couple weeks but as we solved through. The actual court martial which -- -- was very briefly had ninety witnesses and yet it only took two weeks to get through that's because his son didn't really participate. If he carries out that same pattern in the senate -- -- move very quickly as well. The death penalty. Rulings are extremely rare in the military not just the execution itself about fifty years ago but the number of military service members currently on death row. I think if his son gets the death penalty on conviction. Or sentencing excuse me he will -- become only the fifth. Military service member right now on death row so it's extremely rare part of it is has part to do with the automatic reviews that are under way. When there is such a sentencing is -- that is that carried out by cherry. Well certainly in unusual and tragic case NBC's Louis Martinez thank you so much joining -- thanks pentagon. He's been watching ABC news digital special report on -- Hernandez in New York. This has been a special report from me.

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